Simulation of magnetization at finite temperature by the Metropolis method

摘要

The influence of thermal fluctuations onmagnetization properties in thermally assisted magnetic recording is investigated. To achieve high magnetic recording density using thermal assistance, the recording domain is temporarily heated by a laser to allow recording using media with high coercivity at room temperature. A method for calculating the effect of thermal fluctuations based on the Metropolis method is proposed. The method is used to examine the relationship between magnetization of the heated region and the heating temperature, and the change in magnetization during cooling for TbFeCo films. It is found that magnetization reversal is more prominent at high temperature, but is accompanied by increased randomness in the direction of magnetization. In the cooling process, the magnetization reversal with random orientation converges to the center of the target region, forming a concentration of reversed magnetization.